If I wait to FRA to claim benefits and my wife then claims claims spousal benefits before reaching her FRA , what are the ramifications for her potential to receive larger pension benefits in the future?(She has much lower PIA than I do)
If your wife claims spousal benefits before full retirement age (FRA), she'll also be deemed to be filing on her own record and she'll only receive what is essentially the higher of the 2 benefits. Her benefit rate will also be reduced for age, and the earlier she files the more the reduction.
Regardless of when your wife files for her retirement and spousal benefits, however, she could still receive up to your full benefit rate as a widow provided that she is at least FRA when she starts drawing the widows benefits.
It sounds like you and your wife have many potential filing options available to you. You should strongly consider using the maximization software on this website to determine your best overall strategy.